CodeGenDAGPatterns, where it can be used in other tablegen backends.
This allows the inference to be done for DAGISelEmitter so that it
gets accurate mayLoad/mayStore/isSimpleLoad flags.
This brings MemOperand functionality back to where it was before
48329. However, it doesn't solve the problem of anonymous patterns
which expand to code that does loads or stores.
llvm-svn: 49123
were being pruned in patterns where a variable was used more than once, e.g.:
(or (and R32C:$rA, R32C:$rC), (and R32C:$rB, (not R32C:$rC)))
In this example, $rC is used more than once and is actually significant to
instruction selection pattern matching when commuted variants are produced.
This patch scans the pattern's clauses and collects the variables, creating
a set of variables that are used more than once. TreePatternNode::isIsomorphicTo()
also understands that multiply-used variables are significant.
llvm-svn: 47950
tblgen will complain if a sign-extended constant does not fit into a
data type smaller than i32, e.g., i16. This causes a problem when certain
hex constants are used, such as 0xff for byte masks or immediate xor
values.
tblgen will try the sign-extended value first and, if the sign extended
value would overflow, it tries to see if the unsigned value will fit.
Consequently, a software developer can now safely incant:
(XORHIr16 R16C:$rA, 0xffff)
which is somewhat clearer and more informative than incanting:
(XORHIr16 R16C:$rA, (i16 -1))
even if the two are bitwise equivalent.
Tblgen also outputs the 64-bit unsigned constant in the generated ISel code
when getTargetConstant() is invoked.
llvm-svn: 47188
instead of "ISD::STORE". This allows us to mark target-specific dag
nodes as storing (such as ppc byteswap stores). This allows us to remove
more explicit isStore flags from the .td files.
Finally, add a warning for when a .td file contains an explicit
isStore and tblgen is able to infer it.
llvm-svn: 45654
